import { Easing } from 'react-native-reanimated';
import type { DragConfig } from '../types';

/** Enable verbose per-frame drag debug logging. */
export const VERBOSE_DRAG_DEBUG = false;

/** Enable targeted drop/hover debug logs (hover index changes + drop math). */
export const DROP_DEBUG_LOGS = false;

/** Enable drop commit detection logs (UI vs JS commit). */
export const DROP_COMMIT_DEBUG = false;

/** Unified animation timing configuration for consistency across all drag hooks. */
export const ANIMATION_TIMING = {
  SHIFT_DURATION: 100,
  DROP_SETTLE_DURATION: 150,
  SHADOW_FADE_DURATION: 100,
  COMPENSATION_DURATION: 100,
  SHIFT_TO_ZERO_DURATION: 120,
  OVERLAY_SETTLE_DURATION: 120,
  RETURN_TO_ORIGIN_DURATION: 150,
  DROP_SQUISH_DURATION: 80,
  ELEVATION_UP_DURATION: 150,
  ELEVATION_DOWN_DURATION: 150,
} as const;

/** Spring animation configurations for drag interactions. */
export const SPRING_CONFIGS = {
  DRAG_SCALE: { damping: 15, stiffness: 400 },
  DROP_BOUNCE: { damping: 12, stiffness: 300 },
  ELEVATION: { damping: 20, stiffness: 300 },
} as const;

/** Timing animation configurations for drag interactions. */
export const TIMING_CONFIGS = {
  OVERLAY_SETTLE: { duration: ANIMATION_TIMING.OVERLAY_SETTLE_DURATION, easing: Easing.out(Easing.ease) },
  RETURN_TO_ORIGIN: { duration: ANIMATION_TIMING.RETURN_TO_ORIGIN_DURATION, easing: Easing.out(Easing.ease) },
} as const;

/** Configurable thresholds for drag calculations. */
export const DRAG_THRESHOLDS = {
  /** Offset factor for hover position calculation (0-0.5, where 0 = exact center). */
  HOVER_OFFSET_FACTOR: 0.1,
  /** Hysteresis threshold - pointer must move this fraction into next item. */
  HOVER_SWITCH_THRESHOLD: 0.6,
  /** Z-index for elevated (dragged) items. */
  ELEVATED_Z_INDEX: 999,
  /** Minimum shift value to consider significant. */
  SHIFT_SIGNIFICANCE_THRESHOLD: 1,
  /** Epsilon for floating point comparisons (~1/1000 pixel). */
  FLOAT_EPSILON: 0.001,
} as const;

/**
 * Default drag configuration.
 * All values can be overridden via AnimatedFlashList config prop.
 */
export const DEFAULT_DRAG_CONFIG: DragConfig = {
  itemHeight: 95,
  dragScale: 1.03,
  dragShadowOpacity: 0.25,
  itemVerticalMargin: 8,
  longPressDuration: 200,
  edgeThreshold: 80,
  maxScrollSpeed: 10,
  dropBounceScale: 0.97,
  dropHapticEnabled: true,
};

/** Create a merged drag config from defaults and overrides. */
export function createDragConfig(overrides?: Partial<DragConfig>): DragConfig {
  if (!overrides) return DEFAULT_DRAG_CONFIG;
  return { ...DEFAULT_DRAG_CONFIG, ...overrides };
}